561961019 has 2 divisors, whose sum is σ = 561961020. Its totient is φ = 561961018.

The previous prime is 561960991. The next prime is 561961021. The reversal of 561961019 is 910169165.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 561961019 - 2¹⁶ = 561895483 is a prime.

It is a super-2 number, since 2×561961019² = 631600373751036722, which contains 22 as substring.

Together with 561961021, it forms a pair of twin primes.

It is a Chen prime.

It is equal to p_29439506 and since 561961019 and 29439506 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (561961039) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 280980509 + 280980510.

It is an arithmetic number, because the mean of its divisors is an integer number (280980510).

Almost surely, 2^561961019 is an apocalyptic number.

561961019 is a deficient number, since it is larger than the sum of its proper divisors (1).

561961019 is an equidigital number, since it uses as much as digits as its factorization.

561961019 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 14580, while the sum is 38.

The square root of 561961019 is about 23705.7170108816. The cubic root of 561961019 is about 825.2180722570.

The spelling of 561961019 in words is "five hundred sixty-one million, nine hundred sixty-one thousand, nineteen".